The invention relates to the field of sample preparation systems for chemical assays, and, more particularly, to the field of sample preparation chambers or systems that are adapted to handle liquid, solid, granulated or highly viscous samples.
In many chemical processing facilities and laboratories there is a need to do chemical assays on chemical samples. Often these assays are done by means of gas or liquid chromatography. The form in which the samples for analysis come are many and varied. For most chromatography assays, diluted solutions of a homogeneous mixture of the sample and a diluent must be used. If the sample is a solid, it must first be dissolved. If the sample is a two phase liquid/liquid or liquid/solid combination, the mixture must be homogenized. If the sample is viscous, its viscosity must be reduced by dilution so that it may be pumped through the liquid chromatography column. All the samples must be diluted to a known concentration prior to pumping the diluted sample solution through the liquid chromatography column.
It is important in preparing samples for liquid chromatography and other types of assays to know the exact concentration of the sample being supplied to the assay. When dilution is being performed therefore, it is important to be able to isolate a known quantity of the sample. If the same container is to be used for a series of dilutions, it is also important to remove the rest of the sample from the container where the diluted sample is to be stored. To get exact concentrations, it is also necessary to be able to wash out the remnants of the sample from the various tubes in the system and off the walls of the sample container.
For solid samples it is important to be able to grind them to powder and to be able to add solvent to the powder before dissolving it in preparation for dilution to the desired concentration. For two phase samples it is advantageous to be able to use the same mechanism used for the grinding of the solid samples to mix the two phase samples to homogenize them.
Further, for any samples, particularly solid or viscous samples which are too viscous to pump, it is useful to have a sample container that is lightweight, detachable and portable so that it may be taken to the location of the sample and sample may be placed therein. The sample amount may be determined by weighing the cup before and after the sample has been placed therein. The sample container may then be filled with diluent to reduce the viscosity to a useable range.
The prior art sample preparation systems do not have all the capabilities noted above. Basically, the prior art sample preparation systems are designed to handle only ideal samples which are homogeneous liquid. The ability to handle two phase samples, solid samples or very viscous samples has, heretofore been missing from the art. Further, prior art sample preparation chambers do not include means to wash down the walls of the chamber prior to diluting the metered sample, or to isolate a fixed amount of sample immediately following homogenization.